grizz
Venus,
Can you please tell us more about his tooth?
Did it ever have a Root Canal?
Is it capped?
Does it have an open cavity?
Does it have a dental filling?
Is it caused by severe plaque buildup?
Has he seen a dentist? What has his dentist said?
There is just too many possibilities to give any advice on a tooth with such little information about the problem details.
Grizz